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SHIMBO Genya

Faculty of Veterinary Medicine Veterinary Teaching HospitalAssistant Professor

Researcher basic information

■ Degree
  • 博士(獣医学)
■ URL
researchmap URL■ Research Keywords and Fields
Research Keyword
  • 臨床獣医学
  • 画像診断
■ Educational Organization

Career

■ Career
Career
  • Oct. 2023 - Present
    北海道大学 大学院獣医学研究院, 附属動物病院, 助教
  • Apr. 2018 - Present
    Hokkaido University, 附属動物病院, 特任助教
  • Jun. 2015 - Mar. 2018
    Obihiro University of Agriculture and Veterinary Medicine, Animal Medical Center, 勤務獣医師
Educational Background
  • Apr. 2005 - Mar. 2011, Hokkaido University, School of Veterinary Medicine, 獣医学科
Committee Memberships
  • Jun. 2018 - Present
    日本獣医画像診断学会, 検定委員, Society

Research activity information

■ Awards
■ Papers
  • Deep-learning-based automatic liver segmentation using computed tomography images in dogs
    Seungyeon Lee*; Genya Shimbo* (*co-first author); Nozomu Yokoyama; Kensuke Nakamura; Ren Togo; Takahiro Ogawa; Miki Haseyama; Mitsuyoshi Takiguchi
    Frontiers in Veterinary Science, 12, Frontiers Media SA, 21 Oct. 2025
    Scientific journal, Introduction

    Deep learning-based automated segmentation has significantly improved the efficiency and accuracy of human medicine applications. However, veterinary applications, particularly canine liver segmentation, remain limited. This study aimed to develop and validate a deep learning model based on a 3D U-Net architecture for automated liver segmentation in canine abdominal computed tomography (CT) scans.

    Methods

    A total of 221 canine abdominal CT scans were analyzed, comprising 159 cases without hepatic masses and 62 cases with hepatic masses. The model was trained and evaluated using two separate datasets: one containing cases without hepatic masses (Experiment 1) and the other combining cases with and without hepatic masses (Experiment 2).

    Results

    Both experiments demonstrated high segmentation performance, achieving mean Dice similarity coefficients of 0.926 (Experiment 1) and 0.929 (Experiment 2).

    Discussion

    The manual and predicted liver volumes showed excellent agreement, highlighting the potential clinical applicability of this approach.
  • Outcomes and Prognostic Factors in Dogs With Presumed Intracranial Gliomas Treated With Definitive-Intent Intensity Modulated Radiation Therapy: 55 Cases (2014-2023).
    Yohichi Fukuyama; Kenji Hosoya; Sangho Kim; Koangyong Sung; Tatsuya Deguchi; Genya Shimbo; Kazuyoshi Sasaoka; Ryouhei Kinoshita; Mitsuyoshi Takiguchi
    Veterinary and comparative oncology, 25 Aug. 2025, [International Magazine]
    English, Scientific journal, Radiation therapy (RT) is the treatment of choice for canine intracranial gliomas. Recently, modern advanced radiation techniques, including intensity modulated RT (IMRT) and volumetric modulated arc therapy (VMAT), have become widely available in veterinary medicine. However, the glioma-specific therapeutic outcomes of patients treated with modern RT remain unclear. This study aimed to describe survival outcomes and tumour response and to identify whether any treatment, clinical, and imaging factors were predictive of prognosis in dogs with intracranial gliomas treated with definitive-intent IMRT alone. Medical records of dogs with presumed intracranial gliomas that underwent definitive-intent IMRT were retrospectively reviewed. Fifty-five dogs were included. Amongst them, 29 and 26 underwent fractionated RT (FRT) and stereotactic RT (SRT), respectively. In the 44 dogs that underwent follow-up magnetic resonance imaging (MRI), the overall measurable response rate was 77.3%. Clinical improvement was observed in 92% of the dogs. Local tumour regrowth and drop metastases were observed in 17 (30.9%) and 10 dogs (18.2%), respectively. The median overall survival, disease-specific survival, and progression-free survival were 432, 670, and 441 days, respectively. Seven dogs (12.7%) died during RT or within 6 weeks. There was no statistically significant difference in the survival times between FRT and SRT. In the multivariate analysis, poor performance status, tumour location in the diencephalon, and fluid-attenuated inversion recovery heterogeneity were significantly associated with shorter survival times. These findings suggest that definitive-intent RT results in tumour shrinkage and prolonged survival (432 days) with minimal radiation toxicity regardless of the RT protocol used. Performance status and MRI findings can be useful for predicting prognosis.
  • 炎症性蛋白漏出性腸症の犬における血栓塞栓症の発症に関する前向き調査
    大石 寧々; 大田 寛; 華園 究; 三好 健二郎; 横山 望; 新坊 弦也; 板東 麻美; 赤羽根 僚太; 出口 辰弥; 田村 昌大; 山崎 裕毅
    北海道獣医師会雑誌, 68, 8, 314, 314, (公社)北海道獣医師会, Aug. 2024
    Japanese
  • 気管支拡張症の原因として気管支軟骨の低形成が疑われた2頭のアメリカン・コッカー・スパニエル
    川上 侑記; 中村 健介; 菅原 芽伊; 新坊 弦也; 山根 由久; 細谷 謙次; 岡田 一喜; 賀川 由美子; 滝口 満喜
    北海道獣医師会雑誌, 68, 8, 321, 321, (公社)北海道獣医師会, Aug. 2024
    Japanese
  • 部分肺静脈還流異常により右心拡大を呈した犬の1例
    安田 理紗; 中村 健介; 新坊 弦也; 横山 望; 滝口 満喜
    北海道獣医師会雑誌, 68, 8, 323, 323, (公社)北海道獣医師会, Aug. 2024
    Japanese
  • A de novo nonsense variant in the DMD gene associated with X-linked dystrophin-deficient muscular dystrophy in a cat.
    Nozomu Yokoyama; Yuki Matsumoto; Takahisa Yamaguchi; Kazuki Okada; Ryohei Kinoshita; Genya Shimbo; Hisashi Ukawa; Ryuga Ishii; Kensuke Nakamura; Jumpei Yamazaki; Mitsuyoshi Takiguchi
    Journal of veterinary internal medicine, 13 Apr. 2024, [International Magazine]
    English, Scientific journal, BACKGROUND: X-linked dystrophin-deficient muscular dystrophy (MD) is a form of MD caused by variants in the DMD gene. It is a fatal disease characterized by progressive weakness and degeneration of skeletal muscles. HYPOTHESIS/OBJECTIVES: Identify deleterious genetic variants in DMD by whole-genome sequencing (WGS) using a next-generation sequencer. ANIMALS: One MD-affected cat, its parents, and 354 cats from a breeding colony. METHODS: We compared the WGS data of the affected cat with data available in the National Center for Biotechnology Information database and searched for candidate high-impact variants by in silico analyses. Next, we confirmed the candidate variants by Sanger sequencing using samples from the parents and cats from the breeding colony. We used 2 genome assemblies, the standard felCat9 (from an Abyssinian cat) and the novel AnAms1.0 (from an American Shorthair cat), to evaluate genome assembly differences. RESULTS: We found 2 novel high-impact variants: a 1-bp deletion in felCat9 and an identical nonsense variant in felCat9 and AnAms1.0. Whole genome and Sanger sequencing validation showed that the deletion in felCat9 was a false positive because of misassembly. Among the 357 cats, the nonsense variant was only found in the affected cat, which indicated it was a de novo variant. CONCLUSION AND CLINICAL IMPORTANCE: We identified a de novo variant in the affected cat and next-generation sequencing-based genotyping of the whole DMD gene was determined to be necessary for affected cats because the parents of the affected cat did not have the risk variant.
  • Unsupervised Domain Adaptation for Human and Animal Chest X-Ray Bone Suppression.
    Tomohiro Hashimoto; Ayaka Maruo; Shoichiro Sekiguchi; Yoshitaka Ushiku; Genya Shimbo
    IEEE International Symposium on Biomedical Imaging(ISBI), 1, 5, IEEE, 2024
    International conference proceedings
  • Insular dwarfism in horses from the Aegean Sea and the Japanese archipelago
    Keesha M. Ming; Kévin Le Verger; Madeleine Geiger; Thomas Schmelzle; Georgios L. Georgalis; Genya Shimbo; Motoki Sasaki; Satoshi D. Ohdachi; Marcelo R. Sánchez-Villagra
    Mammalian Biology, 2024
    Scientific journal
  • 乳び胸の原因としてリンパ管腫症が疑われた犬の1例
    早坂 郁人; 新坊 弦也; 細谷 謙次; 三木 伸悟; 滝口 満喜
    日本獣医画像診断学会抄録, 73回, np176, np176, (一社)日本獣医画像診断学会, Dec. 2023
    Japanese
  • Successful treatment of acute respiratory failure following hypertensive crisis in a dog with presumed pheochromocytoma or paraganglioma.
    Jun Tamura; Shino Yoshida; Noriyuki Nagata; Genya Shimbo; Norihiko Oyama
    Open veterinary journal, 13, 11, 1465, 1470, Nov. 2023, [International Magazine]
    English, BACKGROUND: Acute respiratory failure has been reported as one of the manifestations of hypertensive crisis in pheochromocytoma in human medicine. In dogs, no reports have been described as acute respiratory failure following hypertensive crisis. Here, we report the clinical presentation, course, and treatment of acute respiratory failure following the hypertensive crisis in a dog with presumed pheochromocytoma or paraganglioma. CASE DESCRIPTION: A 12-year-old neutered male toy poodle was referred for the diagnostic evaluation of a right adrenal gland mass. The dog suddenly exhibited severe dyspnea with abnormal hypertension (systolic blood pressure >200 mmHg) 15 minutes after recovery from the anesthesia for the computed tomography (CT) examination. Pulmonary CT and ultrasonography findings suggested acute onset of severe pulmonary edema. Pulmonary edema was treated with mechanical ventilation (pressure-support ventilation with continuous positive airway pressure) and negative fluid balance after the administration of furosemide. Weaning from mechanical ventilation was successful 24 hours after the onset of respiratory failure. Finally, the dog was discharged 3 days after weaning from ventilation without complications. CONCLUSION: This report outlines a case of acute respiratory failure following a hypertensive crisis requiring mechanical ventilatory management in a dog. The onset and progression of pulmonary edema were extremely rapid. However, improvement in pulmonary edema was also rapid. Hemodynamic stability, in addition to prompt diagnosis and aggressive therapeutic intervention, including mechanical ventilation, may have contributed to the good prognosis of pulmonary edema following hypertensive crisis in a dog, which we attribute to a catecholamine storm.
  • Successful treatment of sclerosing encapsulating peritonitis in a cat using bioresorbable hyaluronate-carboxymethylcellulose membrane after surgical adhesiolysis and long-term prednisolone
    Nozomu Yokoyama; Ryohei Kinoshita; Hiroshi Ohta; Kazuki Okada; Genya Shimbo; Kazuyoshi Sasaoka; Noriyuki Nagata; Noboru Sasaki; Keitaro Morishita; Kensuke Nakamura; Yumiko Kagawa; Mitsuyoshi Takiguchi
    Journal of Feline Medicine and Surgery Open Reports, 9, 2, SAGE Publications, Jul. 2023
    Scientific journal, Case summary

    An 8-year-old neutered male domestic shorthair indoor cat was presented with an 8-week history of intermittent vomiting, anorexia and weight loss that had been unresponsive to supportive treatment. Abdominal ultrasound revealed plication of the small intestine and fluid accumulation proximal to the lesion, and a linear foreign body was suspected. An exploratory celiotomy showed cocoon-like encapsulation of the entire intestine. Surgical adhesiolysis and full-thickness biopsy were performed, and histopathologic examination revealed mild thickening of the visceral peritoneum with fibrin deposition, as well as mild neutrophil and lymphocyte infiltration. These findings were compatible with sclerosing encapsulating peritonitis (SEP). The cat recovered well postoperatively and was discharged the next day. Prednisolone was administered for 7 weeks to prevent recurrence of SEP. Five months after surgery, the cat was re-presented with anorexia and chronic vomiting. Based on the clinical examination findings, recurrent SEP was suspected. At the second surgery, surgical adhesiolysis was repeated and a bioresorbable hyaluronate-carboxymethylcellulose membrane was used to cover the serosal surface and thus prevent adhesion formation. Histopathologic findings of the peritoneal biopsy specimen confirmed SEP. Long-term prednisolone treatment (1 mg/kg for the first dose and 0.5 mg/kg every 48 h for maintenance) was administered postoperatively. The cat survived for more than 1239 days without recurrence.

    Relevance and novel information

    To our knowledge, this is the first report of SEP in a cat with long-term survival. The use of a bioresorbable hyaluronate-carboxymethylcellulose membrane and long-term prednisolone treatment may have prevented short-term and long-term recurrence, respectively, in this case.
  • 常電圧放射線発生装置を用いて治療した口腔内悪性黒色腫の犬の17症例
    田川 道人; 新坊 弦也; 富張 瑞樹; 宮原 和郎
    日本獣医師会雑誌, 76, 3, e55, e61, (公社)日本獣医師会, Mar. 2023
    Japanese
  • A Case of Metastatic Histiocytic Sarcoma in a Dog Treated with Toceranib Phosphate
    Michihito TAGAWA; Genya SHIMBO; Mizuki TOMIHARI; Ken-ichi WATANABE; Yoshiyasu KOBAYASHI
    Journal of the Japan Veterinary Medical Association, 76, 8, e202, e207, Japan Veterinary Medical Association, 2023
    Scientific journal
  • 磁気共鳴スペクトロスコピーは犬の起源不明髄膜脳脊髄炎の予後指標となり得るか
    山口 敬央; 笹岡 一慶; 新坊 弦也; 山根 由久; 永田 矩之; 横山 望; 森下 啓太郎; 佐々木 東; 中村 健介; 滝口 満喜
    北海道獣医師会雑誌, 66, 8, 287, 287, (公社)北海道獣医師会, Aug. 2022
    Japanese
  • 造影CT検査後に非心原性肺水腫を呈した褐色細胞腫を疑う犬の1例
    吉田 紫乃; 田村 純; 永田 矩之; 大山 紀彦; 新坊 弦也; 池中 良徳; 滝口 満喜
    北海道獣医師会雑誌, 66, 8, 289, 289, (公社)北海道獣医師会, Aug. 2022
    Japanese
  • 麻酔中パルスオキシメーター測定異常から舌局所の灌流障害を疑った犬の1例
    田村 純; 湯本 優希; 大山 紀彦; 新坊 弦也; 滝口 満喜
    北海道獣医師会雑誌, 66, 8, 289, 289, (公社)北海道獣医師会, Aug. 2022
    Japanese
  • The use of 4-dimensional magnetic resonance angiography as a noninvasive procedure to diagnose subclavian steal syndrome in a dog.
    Genya Shimbo; Ryosuke Echigo; Mitsuyoshi Takiguchi
    Journal of the American Veterinary Medical Association, 259, 9, 1040, 1042, 01 Nov. 2021, [International Magazine]
    English, Scientific journal, CASE DESCRIPTION: A 5-year-old 4.1-kg (9.0-lb) spayed female Toy Poodle was referred because of a 6-month history of sporadic signs of neck pain. CLINICAL FINDINGS: Diagnostic imaging with MRI and CT revealed a dilated radicular artery connecting the right and left vertebral arteries and causing mild compression of the spinal cord. The left subclavian artery caudal to the origin of the left vertebral artery was absent. Subclavian steal syndrome (SSS) was suspected. TREATMENT AND OUTCOME: The owner declined surgical treatment; thus, the dog was treated conservatively with glucocorticoids and analgesics. Eight months later, the dog's clinical signs were unchanged but palliated with the administration of glucocorticoids and analgesics, and 4-dimensional (4-D) magnetic resonance angiography (MRA) revealed that the left vertebral artery received blood supply from the right vertebral artery through the dilated radicular artery and that the left vertebral artery caudal to this site had retrograde flow and drained into the left subclavian artery, confirming the diagnosis of SSS. The owner again declined surgery, and conservative treatment continued. The dog's condition was unchanged at the last follow-up communication 11 months after 4-D MRA. CLINICAL RELEVANCE: Subclavian steal syndrome is an extremely rare condition in dogs, and our findings suggested that 4-D MRA could be used to definitively diagnose SSS in dogs.
  • Prognostic role of lymphocyte to monocyte ratio in feline high-grade lymphomas.
    Michihito Tagawa; Genya Shimbo; Kazuro Miyahara
    The Canadian veterinary journal = La revue veterinaire canadienne, 62, 10, 1095, 1103, Oct. 2021, [International Magazine]
    English, Scientific journal, The lymphocyte to monocyte ratio (LMR) is a useful prognostic marker of various cancers in human and canine patients. This study aimed to determine whether this ratio could predict disease outcomes in cats with high-grade lymphoma. Medical records of 33 cats diagnosed with high-grade lymphoma were retrospectively analyzed. The prognostic influence of LMR and other clinicopathological data on the time to progression (TTP) and overall survival (OS) was studied using the Kaplan-Meier curves. The optimal cutoff value of this ratio was 3.4, which corresponded to the maximum sensitivity (1.000) and specificity (0.611) of the LMR for predicting median OS days, using receiver operating characteristic analysis. A univariate analysis demonstrated that cats with a low LMR had significant reductions in both TTP [hazard ration (HR) = 3.403, 95% confidence interval (CI): 1.502 to 8.720; P = 0.003] and OS (HR = 3.418, 95% CI: 1.433 to 9.449, P = 0.005). In multivariate analysis, independent predictors of OS included LMR (HR = 2.889, 95% CI: 1.048 to 8.843, P = 0.040), clinical stage (HR = 0.330, 95% CI: 0.118 to 0.960, P = 0.042), and age (HR = 4.151, 95% CI: 1.574 to 11.888, P = 0.004).
  • CT morphology of anomalous systemic arterial supply to normal lung in dogs.
    Genya Shimbo; Mitsuyoshi Takiguchi
    Veterinary radiology & ultrasound : the official journal of the American College of Veterinary Radiology and the International Veterinary Radiology Association, 62, 6, 657, 665, 11 Jul. 2021, [International Magazine]
    English, Scientific journal, Anomalous systemic arterial supply to the normal lung (ASANL) is a rare congenital anomaly in humans, in which the systemic arteries supply the basal segments of the lower lobe. It has a normal bronchial connection, but lacks a normal pulmonary artery. This anomaly has not been previously reported in the veterinary literature. The objectives of this retrospective descriptive study were to characterize the CT findings and clinical features of ASANL , and to determine the breed predisposition in a population of referral canine cases. Thoracic CT images, in which the caudal lung lobes were fully inflated and the pulmonary artery could be traced to the periphery, were reviewed. A total of 1,950 dogs were enrolled, and the aberrant vasculature equivalent to ASANL in humans was detected in 48 dogs. Shetland Sheepdogs (7/48, odds ratio [OR] = 8.0, P < 0.00001), Miniature Dachshunds (19/48, OR = 3.9, P < 0.00001), and Labrador Retrievers (6/48, OR = 4.5, P = 0.0009) were over-represented. The affected lung lobes were the right caudal lobe (24/48, 50%), the left caudal lobe (21/48, 43.8%), and bilateral caudal lobes (3/48, 6.3%). The aberrant vessels originated from the left gastric artery (14/48), descending thoracic aorta (8/48), celiac artery (6/48), and splenic artery (1/48). In the remaining 19 cases, the origin of the aberrant vessels could not be determined. Although the clinical significance of ASANL in dogs remains unclear, surgeons should be aware of this finding prior to lobectomy of the caudal lung lobes to avoid intraoperative systemic arterial bleeding.
  • Morphometric evaluation of canine hepatocellular carcinoma using computed tomography: a promising tool for predicting malignancy.
    Rommaneeya Leela-Arporn; Hiroshi Ohta; Genya Shimbo; Noboru Sasaki; Mitsuyoshi Takiguchi
    The Journal of veterinary medical science, 83, 9, 1459, 1464, 06 Jul. 2021, [Domestic magazines]
    English, Scientific journal, The size of canine focal liver lesions (FLLs) is known to be one of the predicting criteria for malignancy. However, there are discrepancies for the measurement of maximum lesion size, resulting in contradicting results among studies and incidences of false positive outcomes. Thus far, the morphometric changes of FLLs for distinguishing malignancy from benignancy remains undocumented. This study aimed to investigate morphometric characteristics of FLLs using computed tomography (CT). CT images of 40 dogs with histopathological confirmation of 49 liver lesions, including 39 hepatocellular carcinomas and 10 nodular hyperplasias were retrospectively reviewed. The morphometric parameters including size (long and short axis diameters measured on transverse image), shape (measured by long to short axis (L/S) ratio), volume, and surface appearance of a liver lesion were evaluated using univariate and stepwise multivariate analyses, respectively. The results of univariate analysis showed that long and short axis diameters, L/S ratio, volume, and surface appearance of a lesion were significantly different between hepatocellular carcinomas and nodular hyperplasias. Multivariate analysis revealed that short axis diameter (>3.30 cm; odds ratio (OR): 36.1, 95% confidence interval (CI): 3.36-387.05, P=0.0031) and L/S ratio (>1.23; OR: 18.1, 95% CI: 1.61-205.12, P=0.0191) were independent predictors of malignancy, with the area under the curve of 0.9154. These results suggest that the combination of short axis diameter and L/S ratio is a promising tool for predicting liver malignancy with outstanding discriminating ability.
  • Cardiomyopathy in a dog with multicentric lymphoma following treatment with several anthracyclines
    Michihito Tagawa; Genya Shimbo; Akiko Uemura; Kotaro Matsumoto
    OPEN VETERINARY JOURNAL, 11, 1, 6, 10, 2021
    English, Scientific journal
  • Acute monoblastic leukemia in a feline leukemia virus-negative cat.
    Michihito Tagawa; Genya Shimbo; Ken-Ichi Watanabe; Noriyuki Horiuchi; Yoshiyasu Kobayashi; Masaki Maezawa; Kotaro Matsumoto; Kazuro Miyahara
    The Journal of veterinary medical science, 82, 7, 1000, 1005, 31 Jul. 2020, [Peer-reviewed], [Domestic magazines]
    English, Scientific journal, A 12-year-old female domestic short-haired cat was presented due to weight loss, anorexia, and tachypnea. Complete blood count revealed severe anemia, leukocytosis with massive undifferentiated blast cells, and thrombocytopenia. Bone marrow aspiration showed acute myeloid leukemia, subclassified as monoblastic leukemia (M5a) based on the outcomes of the cytochemistry examinations. The SNAP feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) test using whole blood was negative. In addition, FeLV/FIV proviral polymerase chain reaction test using bone marrow aspirate was also negative. Although the cat was treated with doxorubicin, cytosine arabinoside, and prednisolone, anemia did not improve without blood transfusion. The owner declined further treatment after 2 months, and the cat died a few days later.
  • Intramedullary spinal nephroblastoma in a mixed breed dog.
    Michihito Tagawa; Genya Shimbo; Mizuki Tomihari; Masashi Yanagawa; Ken-Ichi Watanabe; Noriyuki Horiuchi; Yoshiyasu Kobayashi; Kazuro Miyahara
    The Journal of veterinary medical science, 82, 7, 917, 921, 18 May 2020, [Peer-reviewed], [Domestic magazines]
    English, Scientific journal, A 1-year-old male mixed breed dog presented for the evaluation of progressive hindlimb paresis. Neurological examination indicated a spinal cord lesion between the 3rd thoracic and 3rd lumbar vertebrae. Magnetic resonance imaging (MRI) revealed an intramedullary spinal cord lesion located at the level of the 1st and 2nd lumbar vertebrae. Following cytoreductive surgery of the mass, palliative radiation therapy was administered. A diagnosis of nephroblastoma was made based on histological examination. After radiation therapy, the disappearance of the spinal lesion was confirmed by MRI. The dog was improved from gait abnormality and alive at 16 months postoperatively, with slight signs of neurological dysfunction.
  • 肺病変を形成した猫骨髄腫関連疾患の1症例
    田川 道人; 上田 裕貴; 新坊 弦也; 松本 高太郎; 宮原 和郎
    北海道獣医師会雑誌, 64, 3, 1, 4, (公社)北海道獣医師会, Mar. 2020
    Japanese
  • Computed tomographic features for differentiating benign from malignant liver lesions in dogs.
    Rommaneeya Leela-Arporn; Hiroshi Ohta; Genya Shimbo; Kiwamu Hanazono; Tatsuyuki Osuga; Keitaro Morishita; Noboru Sasaki; Mitsuyoshi Takiguchi
    The Journal of veterinary medical science, 81, 12, 1697, 1704, 18 Dec. 2019, [Peer-reviewed], [Domestic magazines]
    English, Scientific journal, Thus far, there are few computed tomography (CT) characteristics that can distinguish benign and malignant etiologies. The criteria are complex, subjective, and difficult to use in clinical applications due to the high level of experience needed. This study aimed to identify practical CT variables and their clinical relevance for broadly classifying histopathological diagnoses as benign or malignant. In this prospective study, all dogs with liver nodules or masses that underwent CT examination and subsequent histopathological diagnosis were included. Signalments, CT findings and histopathological diagnoses were recorded. Seventy liver nodules or masses in 57 dogs were diagnosed, comprising 18 benign and 52 malignant lesions. Twenty-three qualitative and quantitative CT variables were evaluated using univariate and stepwise multivariate analyses, respectively. Two variables, namely, the postcontrast enhancement pattern of the lesion in the delayed phase (heterogeneous; odds ratio (OR): 14.7, 95% confidence interval (CI): 0.82-262.03, P=0.0429) and the maximal transverse diameter of the lesion (>4.5 cm; OR: 33.3, 95% CI: 2.29-484.18, P=0.0006), were significantly related to the differentiation of benign from malignant liver lesions, with an area under the curve of 0.8910, representing an accuracy of 88.6%. These findings indicate that features from triple-phase CT can provide information for distinguishing pathological varieties of focal liver lesions and for clinical decision making. Evaluations of the maximal transverse diameter and postcontrast enhancement pattern of the lesion included simple CT features for predicting liver malignancy with high accuracy in clinical settings.
  • Two-dimensional shear wave elastographyによる非侵襲的な犬の肝線維化診断
    田村 昌大; 大田 寛; 大菅 辰幸; 新坊 弦也; 佐々木 東; 森下 啓太郎; 賀川 由美子; 滝口 満喜
    日本獣医麻酔外科学雑誌, 50, Suppl.2, 315, 315, (一社)日本獣医麻酔外科学会, Dec. 2019
    Japanese
  • 唾液腺造影CTおよび術中唾液腺染色が手術支援に有用であった犬の2例
    竹内 恭介; 細谷 謙次; 新坊 弦也; 金 尚昊; 木之下 怜平; 奥村 正裕
    日本獣医麻酔外科学雑誌, 50, Suppl.2, 287, 287, (一社)日本獣医麻酔外科学会, Dec. 2019
    Japanese
  • Quantification of plasma cell-free DNA levels in dogs with various tumors.
    Michihito Tagawa; Genya Shimbo; Hisashi Inokuma; Kazuro Miyahara
    Journal of veterinary diagnostic investigation : official publication of the American Association of Veterinary Laboratory Diagnosticians, Inc, 31, 6, 836, 843, Nov. 2019, [Peer-reviewed], [International Magazine]
    English, Circulating cell-free DNA (cfDNA) is extracellular DNA released into the bloodstream by apoptotic or necrotic tumor cells, with cfDNA determination proposed as a noninvasive, sensitive marker for the diagnosis of human cancer. We evaluated cfDNA quantification as a diagnostic and prognostic tool in dogs with various tumors. We quantified plasma cfDNA concentration by absolute real-time PCR of long interspersed nuclear elements in 50 dogs with malignant tumors, 13 dogs with benign tumors or nodules, and 11 healthy controls. Six patients with malignant tumors were followed-up, and plasma cfDNA was quantified throughout disease progression. We found that plasma cfDNA concentrations were significantly elevated in dogs with malignant tumors compared with dogs with benign nodules or healthy controls. The DNA integrity index (the ratio between long and short cfDNA fragments) was significantly lower in dogs with malignant tumors compared to healthy controls. Significantly higher cfDNA levels and a lower DNA integrity index were observed in dogs with lymphoma or leukemia, hemangiosarcoma, and distant metastasis; cfDNA levels correlated well with clinical stage and tended to increase during or before periods of disease progression, suggesting potential efficacy of cfDNA for the detection of distant metastasis and to monitor the clinical stage of neoplasia.
  • Prognostic Value of lymphocyte-to-monocyte ratio in canine high-grade lymphoma cases
    Michihito Tagawa; Genya Shimbo; Kotaro Matsumoto; Kazuro Miyahara
    World's Veterinary Journal, 9, 3, 218, 229, Scienceline Publication, 01 Sep. 2019
    English, Scientific journal
  • Usefulness of noninvasive shear wave elastography for the assessment of hepatic fibrosis in dogs with hepatic disease.
    Masahiro Tamura; Hiroshi Ohta; Genya Shimbo; Tatsuyuki Osuga; Noboru Sasaki; Keitaro Morishita; Yumiko Kagawa; Mitsuyoshi Takiguchi
    Journal of veterinary internal medicine, 33, 5, 2067, 2074, Sep. 2019, [Peer-reviewed], [International Magazine]
    English, Scientific journal, BACKGROUND: Two-dimensional shear wave elastography (2D-SWE) can noninvasively evaluate hepatic elastic modulus as shear wave velocity (SWV). Additionally, it may predict the presence of clinical relevant hepatic fibrosis (≥F2) in dogs with hepatic disease. OBJECTIVES: To investigate whether SWV measured by 2D-SWE can differentiate between dogs with (≥F2) and without (F0-1) clinically relevant hepatic fibrosis. ANIMALS: Twenty-eight client-owned dogs with hepatic disease and 8 normal healthy Beagle dogs were enrolled. METHODS: In this cross-sectional prospective study, SWVs were measured using 2D-SWE in all dogs. Hepatic fibrosis stages and necroinflammatory activity grades were histopathologically evaluated using a histological scoring scheme that was adapted from the Ishak schema used in human medicine. RESULTS: Median SWVs were significantly higher in dogs with clinically relevant hepatic fibrosis (2.04 m/s; range, 1.81-2.26 m/s) than in healthy dogs (1.51 m/s; range, 1.44-1.66 m/s; P = .007), and dogs without clinically relevant hepatic fibrosis (1.56 m/s; range, 1.37-1.67 m/s; P < .001). However, no significant difference was found in the SWVs between dogs without clinically relevant hepatic fibrosis and healthy dogs (P = .99). Furthermore, median SWVs were not significantly different among dogs with necroinflammatory activity, those without necroinflammatory activity, and healthy dogs (Kruskal-Wallis test, P = .12). CONCLUSIONS AND CLINICAL IMPORTANCE: The 2D-SWE may be useful for predicting the presence of hepatic fibrosis in dogs with hepatic disease.
  • Findings of contrast-enhanced ultrasonography with Sonazoid for cholangiocellular adenoma in three dogs.
    Masahiro Tamura; Kensuke Nakamura; Tatsuyuki Osuga; Genya Shimbo; Noboru Sasaki; Keitaro Morishita; Hiroshi Ohta; Mitsuyoshi Takiguchi
    The Journal of veterinary medical science, 81, 8, 1104, 1108, 09 Aug. 2019, [Peer-reviewed], [Domestic magazines]
    English, Scientific journal, Contrast-enhanced ultrasonography (CEUS) is useful to distinguish benign and malignant focal liver lesions in dogs. Cholangiocellular adenoma is an extremely rare benign tumor in dogs and has not been examined using CEUS with Sonazoid. The aim of this study was to describe findings of CEUS with Sonazoid in three dogs with cholangiocellular adenoma. All three dogs showed contrast defects in the Kupffer phase and these findings mimicked malignant neoplasia during the Kupffer phase. Moreover, all dogs showed early washout and hypoechoic lesions relative to the surrounding normal liver parenchyma in the portal phase. To our knowledge, this is the first study to report that CEUS findings of cholangiocellular adenoma with Sonazoid mimicked malignancy in three dogs.
  • 犬の胸腰部椎間板ヘルニアに合併した脊髄損傷におけるMRI検査所見の経時的変化とその予後に関する検討
    深山 菜月; 越後 良介; 新坊 弦也; 細谷 謙次; 奥村 正裕
    北海道獣医師会雑誌, 63, 8, 346, 346, (公社)北海道獣医師会, Aug. 2019
    Japanese
  • 足根関節の過屈曲を呈した犬の1例
    桜井 雄平; 越後 良介; 新坊 弦也; 石塚 友人; 奥村 正裕
    北海道獣医師会雑誌, 63, 8, 352, 352, (公社)北海道獣医師会, Aug. 2019
    Japanese
  • FeLV陰性であった急性単球性白血病の猫の2症例
    田川 道人; 新坊 弦也; 渡邉 謙一; 堀内 雅之; 古林 与志安; 宮原 和郎
    北海道獣医師会雑誌, 63, 8, 338, 338, (公社)北海道獣医師会, Aug. 2019, [Peer-reviewed]
    Japanese
  • Three-legged radiographic view for evaluating cranioventral lung region in standing calves with bovine respiratory disease.
    Genya Shimbo; Michihito Tagawa; Kotaro Matsumoto; Mizuki Tomihari; Masashi Yanagawa; Yuki Ueda; Hisashi Inokuma; Kazuro Miyahara
    The Journal of veterinary medical science, 81, 1, 120, 126, 25 Jan. 2019, [Peer-reviewed], [Domestic magazines]
    English, Scientific journal, This study proposed a novel radiographic positioning in order to image the cranioventral lung region using a portable X-ray unit and digital radiography system. In the novel position, calves were restrained in a chute and a unilateral forelimb was pulled cranially with the contralateral forelimb tied to the chute; the forelimbs were then spread cranio-caudally as in a scissor position (Three-legged view: TL view). In a preliminary study, we applied the TL view for imaging of 14 clinically healthy calves. In a clinical study, accuracy in detecting cranioventral lung lesions was compared between the standard standing view and the TL view for 19 calves, which were culled from herd; the results of postmortem examination were used as gold standard. Seven evaluators independently interpreted the images. The median (range) number of trials and the time for obtaining optimal position were 2 (1-7) and 263 sec (105-488), respectively in 14 healthy calves. Calves thicker than approximately 40 cm were not considered candidates for TL view in this setting because of difficulty in restraint and the low output of the portable X-ray unit. The TL view improved the detection of consolidation in the cranioventral lung region, compared with the standard view. The TL view was considered an optional view when the cranioventral lung region was an area of interest, because this view was relatively easy to perform and required a small number of personnel, even for large calves.
  • CD3 and CD20 co-expression in a case of canine peripheral T-cell lymphoma with prominent cardiac and peripheral nerve involvement.
    Shotaro Nakagun; Noriyuki Horiuchi; Kenichi Watanabe; Kotaro Matsumoto; Michihito Tagawa; Genya Shimbo; Yoshiyasu Kobayashi
    Journal of veterinary diagnostic investigation : official publication of the American Association of Veterinary Laboratory Diagnosticians, Inc, 30, 5, 779, 783, Sep. 2018, [Peer-reviewed], [International Magazine]
    English, An 8-y 9-mo-old male Pug dog was presented because of anorexia, hindlimb ataxia, vomiting, and progressive weight loss. Clinical examinations revealed atrophic hindlimb muscles with decreased postural reaction, enlargement of the cardiac silhouette and megaesophagus on radiograph, and reduced cardiac contractility on ultrasonography. The dog died 10 d after the initial examination, and an autopsy was performed. Grossly, the heart was enlarged, with multifocal-to-coalescing extensive plaque-like areas of discoloration on the epicardial surface. On cross-section, the ventricles were moderately dilated, and discoloration extended into the myocardium. Peripheral lymph nodes were of normal size. Histologically, atypical lymphoid cells replaced the myocardium and also extensively infiltrated peripheral nerve bundles in various organs. With immunohistochemistry, the neoplastic cells exhibited strong immunoreactivity for CD3 and CD20, and were negative for CD8, granzyme B, CD79α, and Pax5. Double-label immunofluorescence confirmed co-expression of CD3 and CD20 by the neoplastic cells. Molecular clonality analysis presented a clonal T-cell receptor gamma gene rearrangement. The case was diagnosed as a CD3+/CD20+ peripheral T-cell lymphoma with prominent cardiac and peripheral nerve involvement, indicating neurolymphomatosis.
  • Splenic infarction followed by cerebral infarction in a dog
    Shimbo G; Tagawa M; Yamamoto Y; Miyahara K
    Journal of the Japan Veterinary Medical Association, 71, 8, 443, 448, (公社)日本獣医師会, Aug. 2018, [Peer-reviewed]
    Japanese
  • MRI of lobar holoprosencephaly in a cat with hypodipsic hypernatraemia.
    Shimbo G; Tagawa M; Yanagawa M; Miyahara K
    JFMS open reports, 4, 2, 2055116918801602, Jul. 2018, [Peer-reviewed]
  • Effects of scatter correction processing on image quality of portable thoracic radiography in calves
    Genya Shimbo; Michihito Tagawa; Kotaro Matsumoto; Mizuki Tomihari; Kazuro Miyahara
    Japanese Journal of Veterinary Research, 66, 2, 105, 112, Hokkaido University, 01 May 2018, [Peer-reviewed]
    English, Scientific journal
  • Evaluation of grid performance for thoracic radiography in calves using a portable x-ray unit
    Genya Shimbo; Michihito Tagawa; Kotaro Matsumoto; Mizuki Tomihari; Kazuro Miyahara
    Japanese Journal of Veterinary Research, 66, 1, 13, 19, Hokkaido University, 2018, [Peer-reviewed]
    English, Scientific journal
  • Evaluation of costimulatory molecules in dogs with B cell high grade lymphoma.
    Michihito Tagawa; Chihiro Kurashima; Satoshi Takagi; Naoya Maekawa; Satoru Konnai; Genya Shimbo; Kotaro Matsumoto; Hisashi Inokuma; Keiko Kawamoto; Kazuro Miyahara
    PloS one, 13, 7, e0201222, 2018, [Peer-reviewed], [International Magazine]
    English, Scientific journal, B cell high grade lymphoma is the most common hematopoietic malignancy in dogs. Although the immune checkpoint molecules, programmed death-1 (PD-1) and cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4), and immune checkpoint inhibitors have been evaluated for the treatment of various human lymphoid malignancies, the expression of those molecules and their relationship with prognosis remain unknown in canine lymphoma. The objective of this study was to evaluate the expression of costimulatory molecules on peripheral blood lymphocytes and tumor infiltrating lymphocytes, in addition to associated ligand expression in the lymph nodes of patients with B cell multicentric high grade lymphoma. Eighteen patients diagnosed with B cell high grade lymphoma and nine healthy control dogs were enrolled. Flow cytometric analysis revealed that the expression of PD-1 on CD4+ peripheral and tumor infiltrating lymphocytes and CTLA-4 on CD4+ peripheral lymphocytes was significantly higher in the lymphoma group than in the control group. The expression level of CD80 mRNA was significantly lower in the lymphoma group than in the control group. In contrast, there were no significant differences in PD-L1, PD-L2, and CD86 expression between the groups. Dogs with CTLA-4 levels below the cutoff values, which were determined based on receiver operating characteristic curves, on peripheral CD4+, CD8+, and tumor infiltrating CD4+ lymphocytes had significantly longer survival than dogs with values above the cutoff. Although it is uncertain whether the expression of immune checkpoint molecules affect the biological behavior of canine lymphoma, one possible explanation is that PD-1 and CTLA-4 might be associated with the suppression of antitumor immunity in dogs with B cell high grade lymphoma, particularly through CD4+ T cells.
  • Lissencephaly in a Pekingese
    Genya Shimbo; Michihito Tagawa; Eiji Oohashi; Masashi Yanagawa; Kazuro Miyahara
    JOURNAL OF VETERINARY MEDICAL SCIENCE, 79, 10, 1694, 1697, Oct. 2017, [Peer-reviewed]
    English, Scientific journal
  • Fibrinous pericarditis secondary to bacterial infection in a cat
    Michihito Tagawa; Chihiro Kurashima; Genya Shimbo; Hiroshi Omura; Kenji Koyama; Noriyuki Horiuchi; Yoshiyasu Kobayashi; Keiko Kawamoto; Kazuro Miyahara
    JOURNAL OF VETERINARY MEDICAL SCIENCE, 79, 6, 957, 961, Jun. 2017, [Peer-reviewed]
    English, Scientific journal
  • Gene and protein expression of a soluble form of CTLA-4 in a healthy dog
    Michihito Tagawa; Yuhei Yamamoto; Genya Shimbo; Aiko Iguchi; Xuenan Xuan; Mizuki Tomihari; Kazuro Miyahara
    JOURNAL OF VETERINARY MEDICAL SCIENCE, 79, 5, 871, 875, May 2017, [Peer-reviewed]
    English, Scientific journal
  • Ultrasonographic evaluation of depth width ratio (D/W) of benign and malignant mammary tumors in dogs
    Michihito Tagawa; Eiichi Kanai; Genya Shimbo; Mikiya Kano; Hideki Kayanuma
    JOURNAL OF VETERINARY MEDICAL SCIENCE, 78, 3, 521, 524, Mar. 2016, [Peer-reviewed]
    English, Scientific journal
  • ラット脳腫瘍における間欠的低酸素の可視化と放射線感受性に与える影響
    安井博宣; 新坊弦也; 山盛徹; 永根大幹; 趙松吉; 久下祐司; 稲波修
    日本獣医学会学術集会講演要旨集, 152nd, 316, 2011
    English, Research society
■ Other Activities and Achievements
■ Books and other publications
  • ジェネラリストのための犬と猫の消化器診療:イラストとフローチャートで導く円滑なインフォームド・コンセント
    X線検査、造影X線検査、CT検査
    緑書房, Jan. 2026, 9784868110514, [Joint work]
  • 画像とシェーマで学ぶ犬と猫の超音波 Vol.4 頭頸胸部
    咽喉頭
    Jul. 2025, 9784873627991, [Joint work]
  • 猫の超音波検査 描出から診断・治療まで
    EDUWARD Press, May 2024, [Joint work]
  • 画像とシェーマで学ぶ犬と猫の超音波犬と猫の超音波 vol.3 腹部 下巻
    学窓社, Jul. 2023, 9784873627892, [Joint work]
■ Lectures, oral presentations, etc.
  • 画像診断の答え合わせースペシャリストから学ぶ画像×病理×治療ー「下半身のミステリー」
    第24回 JBVP北海道地区大会, 29 Mar. 2026
    [Invited]
  • 撮影成功のカギはここに!犬と猫のX線検査における保定の極意
    第24回 JBVP北海道地区大会, 29 Mar. 2026
    [Invited]
  • 循環器/呼吸器診療におけるCT検査の有用性
    第22回 日本獣医内科学アカデミー学術大会, 20 Feb. 2026
    [Invited]
  • 肝臓の画像診断:造影CT検査
    第22回 日本獣医内科学アカデミー学術大会, 20 Feb. 2026
    [Invited]
  • X線とCTで深掘りしようー猫の呼吸器胸部画像診断ー
    WJVF 2025 16th Annual Meeting, 26 Jul. 2025
    [Invited]
  • X線とCTで深掘りしようー犬の呼吸器胸部画像診断ー
    WJVF2025 16th Annual Meeting, 26 Jul. 2025
    [Invited]
  • 膵臓の解剖と画像診断
    第110回日本獣医麻酔外科学会学術集会, 21 Jun. 2025
    [Invited]
  • 肝胆道系の画像診断ーX線・超音波・CTを駆使した包括的アプローチー
    第76回日本獣医画像診断学会, 14 Jun. 2025
    [Invited]
  • ベーシック消化管の画像診断(X線検査・超音波)
    新坊 弦也
    第21回 日本獣医内科学アカデミー学術大会, 15 Feb. 2025
    [Invited]
  • 犬と猫の違い:胸部レントゲン
    新坊 弦也
    第21回 日本獣医内科学アカデミー学術大会, 15 Feb. 2025
    [Invited]
  • AIが切り拓く画像診断の新時代
    新坊弦也
    第75回 日本獣医画像診断学会, 08 Dec. 2024
    [Invited]
  • 学び直し 上気道X線検査
    新坊弦也
    第20回 日本獣医内科学アカデミー, 25 Feb. 2024
    23 Feb. 2024 - 25 Feb. 2024, [Invited]
  • 肺の画像診断の嘘と真実
    北海道小動物獣医師会 道東ブロックwebセミナー
    18 Feb. 2024, [Invited]
  • X線の保定の仕方教えます
    新坊弦也
    札幌市小動物獣医師会 愛玩動物看護師研修委員会主催セミナー
    Jan. 2024, [Invited]
  • X線撮影 -撮影条件とポジショニングをマスターする-
    新坊 弦也
    日本臨床獣医学フォーラム年次大会2023 ランチョンセミナー, 23 Sep. 2023, Public discourse
    [Invited]
  • レントゲン撮影時の適切な保定方法
    新坊弦也
    第72回 日本獣医画像診断学会, 10 Jun. 2023, Invited oral presentation
    [Invited]
  • 胸部X線診断1. 食道と気管の評価
    新坊 弦也
    第19回日本獣医内科学アカデミー学術大会, Feb. 2023
    17 Feb. 2023 - 21 Mar. 2023, [Invited]
  • 腹部X線診断
    新坊 弦也
    第19回日本獣医内科学アカデミー学術大会
    17 Feb. 2023 - 21 Mar. 2023, [Invited]
  • 胸部X線診断2. 肺野の評価
    新坊 弦也
    第19回日本獣医内科学アカデミー学術大会
    17 Feb. 2023 - 21 Mar. 2023, [Invited]
  • X線撮影の基本 ーそのポジショニングで良いのですか?ー
    新坊弦也
    第43回動物臨床医学会 ランチョンセミナー, 19 Nov. 2022, Invited oral presentation
    [Invited], [Domestic Conference]
  • X線が読めるようになるための、たった一つのポイント
    第28回北海道小動物獣医師会年次大会, 06 Nov. 2022
    06 Nov. 2022, [Invited]
  • 発育期骨疾患のX線検査
    新坊弦也
    第18回日本獣医内科学アカデミー
    18 Feb. 2022 - 21 Mar. 2022, [Invited]
  • 下気道疾患リレー CTについて
    新坊弦也
    第18回日本獣医内科学アカデミー学術大会
    18 Feb. 2022 - 21 Mar. 2022, [Invited]
  • 下気道疾患リレー X線について
    新坊弦也
    第18回日本獣医内科学アカデミー学術大会
    18 Feb. 2022 - 21 Mar. 2022, [Invited]
  • 頭頸部のX線検査〜撮影技術から読影まで〜
    新坊弦也
    第42回動物臨床医学会年次大会, Invited oral presentation
    11 Nov. 2021 - 05 Dec. 2021, [Invited]
  • 胸部X線読影1, 2, 3
    新坊 弦也
    第17回 日本獣医内科学アカデミー, Feb. 2021, Public discourse
    19 Feb. 2021 - 21 Mar. 2021, [Invited]
  • 犬猫における消化器のX線検査
    新坊 弦也
    令和2年度 日本獣医師会獣医学術学会年次大会オンラインセミナー, 13 Mar. 2021, Public discourse
    [Invited]
  • 頭頸部のX線とCT 撮像から読影まで
    新坊 弦也
    第41回 動物臨床医学会年次大会, Nov. 2020, Public discourse
    22 Nov. 2020 - 23 Nov. 2020, [Invited]
  • 胸部X線読影
    新坊弦也
    第16回 日本獣医内科学アカデミー, 22 Feb. 2020, Public discourse
    21 Feb. 2020 - 23 Feb. 2020, [Invited]
  • 胸部レントゲン撮影!撮影技術から読影まで
    第40回動物臨床医学会記念年次大会, 15 Nov. 2019, Public discourse
    [Invited]
  • 腹部・胸部レントゲン〜撮影と読影の基礎〜
    新坊 弦也
    第15回獣医内科学アカデミー学術大会, 16 Feb. 2019
    [Invited]
  • 結果の出せる画像診断法
    新坊弦也
    北海道獣医師会十勝支部主催小動物関連講習会, 27 Nov. 2016, Japanese, Public discourse
    [Invited], [Domestic Conference]
■ Syllabus
  • 伴侶動物獣医療実習, 2024年, 学士課程, 獣医学部
  • 基本医学総論, 2024年, 修士課程, 医学院
  • プレクリニカル実習, 2024年, 学士課程, 獣医学部
  • 医学総論, 2024年, 博士後期課程, 医学院
  • 伴侶動物獣医療実習Ⅰ, 2024年, 学士課程, 獣医学部
  • 総合専門臨床特論, 2024年, 博士後期課程, 獣医学院
  • 伴侶動物獣医療実習Ⅱ, 2024年, 学士課程, 獣医学部
  • 伴侶動物獣医療実習Ⅰ, 2024年, 学士課程, 獣医学部
  • 夜間・救急獣医療実習Ⅰ, 2024年, 学士課程, 獣医学部
  • 伴侶動物獣医療実習Ⅱ, 2024年, 学士課程, 獣医学部
  • 総合獣医療実習, 2024年, 学士課程, 獣医学部
  • 夜間・救急獣医療実習Ⅰ, 2024年, 学士課程, 獣医学部
  • 総合獣医療実習, 2024年, 学士課程, 獣医学部
  • アドバンスト演習, 2024年, 学士課程, 獣医学部
  • アドバンスト演習, 2024年, 学士課程, 獣医学部
  • アドバンスト演習, 2024年, 学士課程, 獣医学部
  • プレクリニカル実習, 2024年, 学士課程, 獣医学部
  • 放射線獣医療・画像診断学, 2024年, 学士課程, 獣医学部
■ Affiliated academic society
  • THE JAPANESE SOCIETY OF VETERINARY SCIENCE
  • JAPAN VETERINARY MEDICAL ASSOCIATION
  • THE JAPANESE SOCIETY OF VETERINARY IMAGINGS
■ Research Themes
  • 犬の胸部X線画像における体位非依存型骨陰影抑制の開発
    科学研究費助成事業
    01 Apr. 2026 - 31 Mar. 2030
    新坊 弦也
    日本学術振興会, 基盤研究(C), 北海道大学, 26K09100
  • 副腎皮質機能亢進症関連肝障害による肝細胞癌発症機序の解明
    科学研究費助成事業
    01 Apr. 2023 - 31 Mar. 2026
    滝口 満喜; 村上 正晃; 佐々木 東; 新坊 弦也; 横山 望
    日本学術振興会, 基盤研究(B), 北海道大学, 23K27067
  • 副腎皮質機能亢進症関連肝障害による肝細胞癌発症機序の解明
    科学研究費助成事業
    01 Apr. 2023 - 31 Mar. 2026
    滝口 満喜; 村上 正晃; 佐々木 東; 新坊 弦也; 横山 望
    日本学術振興会, 基盤研究(B), 北海道大学, 23H02374
  • 伴侶動物のCT画像における人工知能を用いたsegmentation手法の開発
    科学研究費助成事業 若手研究
    01 Apr. 2023 - 31 Mar. 2026
    新坊 弦也
    日本学術振興会, 若手研究, 北海道大学, 23K14074
  • 人工知能による伴侶動物のX線像におけるBone Suppression処理の開発
    科学研究費助成事業 若手研究
    01 Apr. 2020 - 31 Mar. 2023
    新坊 弦也
    昨年度に引き続き、骨成分抽出モデルの精度向上に取り組んだ。昨年度は擬似X線画像を実際のX線画像に近似させる方策をとったものの、臨床応用に耐えうるレベルの精度が得られなかった。そこで、今年度は実際のX線画像の画像処理を解除することにより、X線画像を擬似X線画像側に近似させることにより精度の向上を図った。しかし、得られた骨成分抽出モデルの精度は昨年度のものと比較して向上しなかった。マシンパワーの制約により、骨成分抽出モデルは擬似X線画像を複数のパッチワーク状に分割して学習させていたが、分割された画像は領域によって大きく外観が異なることから、単一の学習モデルを複数の領域に適用させたことが精度向上の足枷になっているのではないかと考えた。そこで、分割した画像を脊椎領域、肺野、腹部、その他の領域にラベル付けし、それぞれ異なる学習モデルを適用することにより精度の向上を図った。これにより、骨成分抽出モデルは「脊椎抽出モデル」、「肋骨抽出モデル」、「腹部における脊椎抽出モデル」、「その他の骨成分抽出モデル」と役割を細分化することとなり、より学習データの汎化性の低い学習となる。この手法ではまず分割した画像のラベル付け作業が膨大となるため、ラベル付け自体をResNetを用いた学習モデルを作成することにより自動化することを図った。一方で、CT画像の収集は継続しており、ネコにおいては現時点で270例のCT画像を収集している。今年度収集したCT画像は学習データセットに組み込むには至っていない。
    日本学術振興会, 若手研究, 北海道大学, 20K15673
  • 深層学習を用いた伴侶動物の胸部X線画像におけるBone Suppression処理の開発
    第8回北海道大学部局横断シンポジウム研究助成採択 銅賞
    Oct. 2022 - Oct. 2022
    Shimbo G, Maruo A, Kato C
    北海道大学, Principal investigator
  • 人獣連携によりMR画像-CT画像変換を高精度化する技術の開発~前立腺癌に対するMR画像誘導即時適応尿道線量低減陽子線治療の実現に向けて~
    第8回北海道大学部局横断シンポジウム研究助成採択 銅賞
    Oct. 2022 - Oct. 2022
    Yoshimura T, Shinbo G, Matsuura T, Hashimoto T, Nishioka K, Mori T, Kanehira T, Sugimori H
    北海道大学, Coinvestigator
■ Academic and Social Contribution Activities/Other
Social Contribution Activities
  • Fundamentals of Gastrointestinal Radiographic Interpretation
    21 Mar. 2025
    Lecturer
    ザンビア獣医師会
  • 認定医講習 骨格レントゲン読影法1,2
    07 Dec. 2024
    Lecturer
    第75回 日本獣医画像診断学会
  • Nontraditional Interpretation of Lung Patterns
    21 Jun. 2024
    Lecturer
    ザンビア獣医師会
  • 頭頸部のX線と超音波
    17 Jan. 2024
    Lecturer
    北海道大学動物医療センター 卒後教育セミナ
  • 下部呼吸器疾患のX線診断
    21 Nov. 2018
    Lecturer
    北海道大学動物医療センター
    卒後教育セミナー